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Developmental Biology Jun 2021Mammalian post-implantation development comprises the coordination of complex lineage decisions and morphogenetic processes shaping the embryo. Despite technological... (Review)
Review
Mammalian post-implantation development comprises the coordination of complex lineage decisions and morphogenetic processes shaping the embryo. Despite technological advances, a comprehensive understanding of the dynamics of these processes and of the self-organization capabilities of stem cells and their descendants remains elusive. Building synthetic embryo-like structures from pluripotent embryonic stem cells in vitro promises to fill these knowledge gaps and thereby may prove transformative for developmental biology. Initial efforts to model the post-implantation embryo resulted in structures with compromised morphology (gastruloids). Recent approaches employing modified culture media, an extracellular matrix surrogate or extra-embryonic stem cells, however, succeeded in establishing embryo-like architecture. For example, embedding of gastruloids in Matrigel unlocked self-organization into trunk-like structures with bilateral somites and a neural tube-like structure, together with gut tissue and primordial germ cell-like cells. In this review, we describe the currently available models, discuss how these can be employed to acquire novel biological insights, and detail the imminent challenges for improving current models by in vitro engineering.
Topics: Animals; Embryo, Mammalian; Embryonic Development; Extracellular Matrix; Humans; Morphogenesis; Organoids; Pluripotent Stem Cells
PubMed: 33347872
DOI: 10.1016/j.ydbio.2020.12.015 -
Cardiovascular Research Jul 2023Congenital heart disease (CHD) is the most common genetic birth defect, which has considerable morbidity and mortality. We focused on deciphering key regulators that...
AIMS
Congenital heart disease (CHD) is the most common genetic birth defect, which has considerable morbidity and mortality. We focused on deciphering key regulators that govern cardiac progenitors and cardiogenesis. FOXK1 is a forkhead/winged helix transcription factor known to regulate cell cycle kinetics and is restricted to mesodermal progenitors, somites, and heart. In the present study, we define an essential role for FOXK1 during cardiovascular development.
METHODS AND RESULTS
We used the mouse embryoid body system to differentiate control and Foxk1 KO embryonic stem cells into mesodermal, cardiac progenitor cells and mature cardiac cells. Using flow cytometry, immunohistochemistry, cardiac beating, transcriptional and chromatin immunoprecipitation quantitative polymerase chain reaction assays, bulk RNA sequencing (RNAseq) and assay for transposase-accessible chromatin using sequencing (ATACseq) analyses, FOXK1 was observed to be an important regulator of cardiogenesis. Flow cytometry analyses revealed perturbed cardiogenesis in Foxk1 KO embryoid bodies (EBs). Bulk RNAseq analysis at two developmental stages showed a significant reduction of the cardiac molecular program in Foxk1 KO EBs compared to the control EBs. ATACseq analysis during EB differentiation demonstrated that the chromatin landscape nearby known important regulators of cardiogenesis was significantly relaxed in control EBs compared to Foxk1 KO EBs. Furthermore, we demonstrated that in the absence of FOXK1, cardiac differentiation was markedly impaired by assaying for cardiac Troponin T expression and cardiac contractility. We demonstrate that FOXK1 is an important regulator of cardiogenesis by repressing the Wnt/β-catenin signalling pathway and thereby promoting differentiation.
CONCLUSION
These results identify FOXK1 as an essential transcriptional and epigenetic regulator of cardiovascular development. Mechanistically, FOXK1 represses Wnt signalling to promote the development of cardiac progenitor cells.
Topics: Animals; Mice; Cell Differentiation; Embryonic Stem Cells; Heart; Wnt Signaling Pathway
PubMed: 37036809
DOI: 10.1093/cvr/cvad054 -
Developmental Dynamics : An Official... Jan 2021In vertebrates, the trunk consists of the musculoskeletal structures of the back and the ventrolateral body wall, which together enclose the internal organs of the... (Review)
Review
In vertebrates, the trunk consists of the musculoskeletal structures of the back and the ventrolateral body wall, which together enclose the internal organs of the circulatory, digestive, respiratory and urogenital systems. This review gives an overview on the development of the thoracic and abdominal wall during amniote embryogenesis. Specifically, I briefly summarize relevant historical concepts and the present knowledge on the early embryonic development of ribs, sternum, intercostal muscles and abdominal muscles with respect to anatomical bauplan, origin and specification of precursor cells, initial steps of pattern formation, and cellular and molecular regulation of morphogenesis.
Topics: Abdominal Muscles; Abdominal Wall; Animals; Humans; Intercostal Muscles; Ribs; Sternum; Thoracic Wall; Vertebrates
PubMed: 32406962
DOI: 10.1002/dvdy.193 -
Toxicology and Applied Pharmacology Feb 20232,4-di-tert-butylphenol (2,4-DTBP) is a synthetic antioxidant used in polyethylene crosspolymer (PEX) water distribution pipes and food-related plastics. 2,4-DTBP can...
2,4-di-tert-butylphenol (2,4-DTBP) is a synthetic antioxidant used in polyethylene crosspolymer (PEX) water distribution pipes and food-related plastics. 2,4-DTBP can leach from plastic materials and has been found in breast milk, cord blood, and placental tissue, giving rise to the concern that this compound may interfere with fetal development. The objective of this study is to assess the impacts of 2,4-DTBP on cellular differentiation. Human induced pluripotent stem (HiPS) cells were differentiated into osteoblasts or myoblasts over 40 days, and analyzed for markers of somite, dermomyotome, sclerotome, myoblast, and osteoblast development. When cultured as stem cells, 2,4-DTBP did not alter cell viability and expression of markers (NANOG, OCT4). However, upon differentiation into somite-like cells, 2,4-DTBP had reduced levels of MEOX1 and TBX6 transcripts, while NANOG and OCT4 were in turn upregulated in a dose-dependent manner. At the sclerotome-like stage, PAX9 mRNA decreased by 2-fold in the 0.5 μM and 1.0 μM 2,4-DTBP exposure groups. After 40 days of differentiation into an osteoblast-like lineage, exposure to 2,4-DTBP significantly reduced expression of the osteogenesis transcripts RUNX2 and OSX in a dose-dependent manner. Further, Alizarin Red staining of calcium deposits was decreased in the 0.5 μM and 1.0 μM treatment groups. In contrast, myogenesis was not affected by 2,4-DTBP exposure. Interestingly, KEAP1 expression was significantly increased in the sclerotomal-like cells, but decreased in the dermomytomal-like cells, which may suggest a mechanism of action. Overall, this study shows that 2,4-DTBP can delay key processes during sclerotome and osteoblast development, leading to a potential for bone developmental issues in exposed individuals.
Topics: Female; Pregnancy; Humans; Osteogenesis; Kelch-Like ECH-Associated Protein 1; NF-E2-Related Factor 2; Placenta; Cell Differentiation; Plastics; Osteoblasts; Cells, Cultured
PubMed: 36682590
DOI: 10.1016/j.taap.2023.116386 -
Frontiers in Cell and Developmental... 2021Embryonic myogenesis is a temporally and spatially regulated process that generates skeletal muscle of the trunk and limbs. During this process, mononucleated myoblasts... (Review)
Review
Embryonic myogenesis is a temporally and spatially regulated process that generates skeletal muscle of the trunk and limbs. During this process, mononucleated myoblasts derived from myogenic progenitor cells within the somites undergo proliferation, migration and differentiation to elongate and fuse into multinucleated functional myofibers. Skeletal muscle is the most abundant tissue of the body and has the remarkable ability to self-repair by re-activating the myogenic program in muscle stem cells, known as satellite cells. Post-transcriptional regulation of gene expression mediated by RNA-binding proteins is critically required for muscle development during embryogenesis and for muscle homeostasis in the adult. Differential subcellular localization and activity of RNA-binding proteins orchestrates target gene expression at multiple levels to regulate different steps of myogenesis. Dysfunctions of these post-transcriptional regulators impair muscle development and homeostasis, but also cause defects in motor neurons or the neuromuscular junction, resulting in muscle degeneration and neuromuscular disease. Many RNA-binding proteins, such as members of the muscle blind-like (MBNL) and CUG-BP and ETR-3-like factors (CELF) families, display both overlapping and distinct targets in muscle cells. Thus they function either cooperatively or antagonistically to coordinate myoblast proliferation and differentiation. Evidence is accumulating that the dynamic interplay of their regulatory activity may control the progression of myogenic program as well as stem cell quiescence and activation. Moreover, the role of RNA-binding proteins that regulate post-transcriptional modification in the myogenic program is far less understood as compared with transcription factors involved in myogenic specification and differentiation. Here we review past achievements and recent advances in understanding the functions of RNA-binding proteins during skeletal muscle development, regeneration and disease, with the aim to identify the fundamental questions that are still open for further investigations.
PubMed: 34616743
DOI: 10.3389/fcell.2021.738978 -
Nature Communications Sep 2023Understanding of the molecular drivers of lineage diversification and tissue patterning during primary germ layer development requires in-depth knowledge of the dynamic...
Understanding of the molecular drivers of lineage diversification and tissue patterning during primary germ layer development requires in-depth knowledge of the dynamic molecular trajectories of cell lineages across a series of developmental stages of gastrulation. Through computational modeling, we constructed at single-cell resolution, a spatio-temporal transcriptome of cell populations in the germ-layers of gastrula-stage mouse embryos. This molecular atlas enables the inference of molecular network activity underpinning the specification and differentiation of the germ-layer tissue lineages. Heterogeneity analysis of cellular composition at defined positions in the epiblast revealed progressive diversification of cell types. The single-cell transcriptome revealed an enhanced BMP signaling activity in the right-side mesoderm of late-gastrulation embryo. Perturbation of asymmetric BMP signaling activity at late gastrulation led to randomization of left-right molecular asymmetry in the lateral mesoderm of early-somite-stage embryo. These findings indicate the asymmetric BMP activity during gastrulation may be critical for the symmetry breaking process.
Topics: Animals; Mice; Gastrulation; Functional Laterality; Gastrula; Germ Layers; Mesoderm
PubMed: 37709743
DOI: 10.1038/s41467-023-41482-5 -
MicroPublication Biology 2022The group of Fibronectin type III domain-containing (FNDC; InterPro IPR003961) protein super family splits into a large number of gene-orthologues and mediates a variety...
The group of Fibronectin type III domain-containing (FNDC; InterPro IPR003961) protein super family splits into a large number of gene-orthologues and mediates a variety of cellular functions during development and disease. They act as anti-inflammatory factors, are linked to cell-cell-interactions, regulate cell signaling and are associated with different cancer types, like cervical and colorectal. One member of this gene family is , which influences different developmental processes in vertebrates, like Sertoli cell/spermatid adhesion in mice testis, bone traits in chicken, and fin development in zebrafish. To identify downstream molecular processes during vertebrate development we investigated gene expression profiles in the previously established zebrafish mutants via microarray analyses on 22 hpf embryos (26-somite stage). Our analyses imply distinct transcriptional profiles between genotype groups and hint to altered cell binding and catalytic activity in mutants.
PubMed: 36254247
DOI: 10.17912/micropub.biology.000646 -
Developmental Cell Oct 2023The mammalian body plan is shaped by rhythmic segmentation of mesoderm into somites, which are transient embryonic structures that form down each side of the neural...
The mammalian body plan is shaped by rhythmic segmentation of mesoderm into somites, which are transient embryonic structures that form down each side of the neural tube. We have analyzed the genome-wide transcriptional and chromatin dynamics occurring within nascent somites, from early inception of somitogenesis to the latest stages of body plan establishment. We created matched gene expression and open chromatin maps for the three leading pairs of somites at six time points during mouse embryonic development. We show that the rate of somite differentiation accelerates as development progresses. We identified a conserved maturation program followed by all somites, but somites from more developed embryos concomitantly switch on differentiation programs from derivative cell lineages soon after segmentation. Integrated analysis of the somitic transcriptional and chromatin activities identified opposing regulatory modules controlling the onset of differentiation. Our results provide a powerful, high-resolution view of the molecular genetics underlying somitic development in mammals.
Topics: Pregnancy; Female; Mice; Animals; Somites; Embryonic Development; Mesoderm; Cell Differentiation; Chromatin; Mammals
PubMed: 37499658
DOI: 10.1016/j.devcel.2023.07.003 -
Developmental Cell Jun 2024Development consists of a highly ordered suite of steps and transitions, like choreography. Although these sequences are often evolutionarily conserved, they can display... (Review)
Review
Development consists of a highly ordered suite of steps and transitions, like choreography. Although these sequences are often evolutionarily conserved, they can display species variations in duration and speed, thereby modifying final organ size or function. Despite their evolutionary significance, the mechanisms underlying species-specific scaling of developmental tempo have remained unclear. Here, we will review recent findings that implicate global cellular mechanisms, particularly intermediary and protein metabolism, as species-specific modifiers of developmental tempo. In various systems, from somitic cell oscillations to neuronal development, metabolic pathways display species differences. These have been linked to mitochondrial metabolism, which can influence the species-specific speed of developmental transitions. Thus, intermediary metabolic pathways regulate developmental tempo together with other global processes, including proteostasis and chromatin remodeling. By linking metabolism and the evolution of developmental trajectories, these findings provide opportunities to decipher how species-specific cellular timing can influence organism fitness.
PubMed: 38906137
DOI: 10.1016/j.devcel.2024.05.027 -
PLoS Genetics Jun 2023Four SIX homeoproteins display a combinatorial expression throughout embryonic developmental myogenesis and they modulate the expression of the myogenic regulatory...
Four SIX homeoproteins display a combinatorial expression throughout embryonic developmental myogenesis and they modulate the expression of the myogenic regulatory factors. Here, we provide a deep characterization of their role in distinct mouse developmental territories. We showed, at the hypaxial level, that the Six1:Six4 double knockout (dKO) somitic precursor cells adopt a smooth muscle fate and lose their myogenic identity. At the epaxial level, we demonstrated by the analysis of Six quadruple KO (qKO) embryos, that SIX are required for fetal myogenesis, and for the maintenance of PAX7+ progenitor cells, which differentiated prematurely and are lost by the end of fetal development in qKO embryos. Finally, we showed that Six1 and Six2 are required to establish craniofacial myogenesis by controlling the expression of Myf5. We have thus described an unknown role for SIX proteins in the control of myogenesis at different embryonic levels and refined their involvement in the genetic cascades operating at the head level and in the genesis of myogenic stem cells.
Topics: Mice; Animals; Homeodomain Proteins; Cell Differentiation; Somites; Muscle Development; Gene Expression Regulation, Developmental; Muscle, Skeletal
PubMed: 37267426
DOI: 10.1371/journal.pgen.1010781